What if you made jail like a subcity. While in prison you can still mug other inmates or perform other crimes that earn rep, respect or cash (e.g. push drugs, murder guards/inmates, make toilet wine, etc). But the punishments for failure are more severe: guard extorts you and you owe 10% on all money you make outside of jail for the next 7 days, you get hospitalized for longer without the chance of revival or med help, increased jail time or solitary confinement where you can't do other jail stuff.
You could take it further and even have factions involved (organized crime: bribe/kill warden, war: extra respect boost for going to prison just to shank opposing teams people, etc). You could even expand jobs to include guards, or other such personnel to give bonus to yourself or faction members while they are in prison or to make certain crimes possible. Another crime or OC could be cause riot to bust multiple players from prison and they owe you/your faction money.
And don't even get me started on all the wonderful flavor texts... possibilities abound.